Need Advice: Foundation for Log Garage/Barn

skylog · December 21, 2004, 03:34:32 PM

I'm drawing up plans for a log garage/barn (piece-en-piece), but am concerned about the foundation and the sill.

If I lay my sill log on top of the slab foundation (w/ vapor barrier between) it will only be a couple of inches removed from the ground and will be subject to large amounts of moisture.

If I were to lay a layer of cinderblock around the perimiter of the slab, and then lay the vapor barrier and sill log on top of that, would it make a difference? Would the mortar-only bond between the bottom of the cinder block and the slab be strong enough, or would it compromise the integrity of the structure? Should I treat the sill log w/ something like borate or not bother?

It is possible that I will be using hardwood (probably oak of some sort, but haven't figured out where to buy logs for this project yet), but only if I can find it cheaper than eastern white pine is to buy and truck in. Oak isn't prohibitive because I am able to use mostly short logs because of this particular building method, and I understand that short logs are usually considered undesirable for building - just have to find out who has them. I don't want to use conventional lumber for the sill as that would look out-of-place.

Any and all advice is appreciated. In case it matters, the posts will be tenoned into the sill log and pegged (or bolted) through the tenon. The sill log will be anchored to the foundation using recessed anchor bolts.

Also, I have to keep in mind that - if I can talk my wife into it - this will be the structure that my family and I will be living in while we build our home, so I want to be very careful about the quality of its construction and the ability to keep the inside environment WARM and DRY.

Don P · December 21, 2004, 08:05:55 PM

Welcome Skylog,
Will this work? Don't forget to check with inspections ;)

skylog · December 21, 2004, 08:13:06 PM

Hey DonP: Thanks for the input. Question though? If I did it that way, how would I seal the gap between the slab and the foundation wall I am building? Mortar? I don't want any moisture to come up through that gap. Maybe there wouldn't be enough of a gap to worry about, since I am guessing I'd pour the slab after the footings and mini foundation wall. I do like your idea though, just want to make sure I'm covering every angle. This would also require me to use more concrete than I was anticipating.

Don P · December 21, 2004, 08:25:32 PM

The expansion joint between stemwall and slab is usually "broken" with celotex blackboard, rubber, foam or the like. It can be caulked with something like a good polyurethane . The slab can be dowelled into the stemwall with rebar. There should be 4" of gravel and a vapor barrier under the slab to prevent moisture problems.

Furby · December 21, 2004, 08:32:13 PM

Welcome skylog!
Sorry but I have to ask what it is you are building? I read your first post, and the first thing that jumped into my head was a log cabin type garage. Then you went on to talk about posts and such. Are you building a timber frame garage?

The footing/ wall/ slab drawing Don P showed, is what is used here for all attached garages. There will not be a gap between the wall and slab, other then maybe a small crack from shrinkage. You pour the slab right up against the wall.
If you use proper fill for back filling, there should not be any water issues, unless you build in a low spot or something. Then it really don't matter how ya buid it, it will leak. :

skylog · December 21, 2004, 09:03:55 PM

Hey Furby - thanks for the welcome.

I'm building (or will be) a modular post & beam garage with a loft that will include living quarters (probably just a studio unless I put up some walls). It's the style described in James Mitchell's book "The Craft of Modular Post & Beam".

It's a traditional timber post and beam system (piece-en-piece) that uses half-timber infill walls with tenons/tounges that "slide" into slots/grooves that have been routed on the posts.

Furby · December 21, 2004, 09:15:12 PM

Cool! 8) 8) 8)

I'll have to look that book up. Haven't had much time to do any reading outside of the FF for a looooong time. Been thinking about putting in something at the the lake though, and some type of log, or timber framed cabin is what I have been leaning towards.

skylog · December 21, 2004, 09:21:03 PM

Furby, this style of building lends itself well to one-man doing most of the work. You ought to check the book out. It is the single best book I've read on log construction so far and by far, though I've only read 4 or 5.

Silverback · December 22, 2004, 12:10:06 PM

Skylog. Where are you at in Missouri? You shouldn't have any problems finding most any specie of oak you want. Up in the northern part there are very few grade mills and a bunch of it (I cringe as I type this) goes into palet mills. In southern missouri quite a bit of it goes into tie production. I would recommend white oak if you are going to infill the walls and leave the timbers expose. White oak often goes to stave (barrels) mills in both north and south Missouir.

God I wish I was back in Missouri right now instead of Kansas. I have the need to see some Hickory and Oak.

skylog · December 22, 2004, 01:40:42 PM

Hey Silverback - Originally I'm from southern MO, down around Roaring River State Park. I'm in the south part of Kansas City, MO right now (married a city girl), but we're looking at land over in Miami County, KS to build on. We also like the Leavenworth areas for the schools, but land is getting kind of pricey over there. We're not real picky about where we find land as long as it is close to some good schools and isn't too far away from the Metro - my wife has a thing about being close to a good hospital.

I see that you're over in Manhattan, which means I'm closer to you than most of the rest of Missouri. Question - do you have access to logs or know anyone in the area who does? I could use some help finding resources around here.

And you're right about the oak being used for railroad ties down in the south part of MO. I actually found a mill close to my home town of Cassville that did almost exclusively ties. I decided that I could use these for my project since I don't need long logs, but they only cut the ties to 8' and wouldn't do a run for me at 10'. They were also red oak, which I've heard mixed things about, but I could make do. I could also probably build with 8' ties, but that would just be extra work and overbuilding with more posts. In any case, if you have any suggestions over sources of logs in the area, I'm all ears. I will consider any type of log - especially since this will be a garage (though we will likely be living in it for at least a year).

Silverback · December 22, 2004, 04:07:26 PM

I don't know too many people in Kansas. In the Moberly, Missouri area (30 miles north of Columbia) there is a family of loggers by the name of Bell. Kevin Bell, Brian Bell, and Tom Bell. They are fairly honest (but not completely). I know a guy with a woodmizer in the Moberly area but he is so strange that I would not send anybody to him unaccompanied. I know some Amish in that area who have a mill; they can cut up to 22'. I could get their postal address. The only problem is that they don't have a phone. There is one guy between Manhattan and Topeka that retails grade wood that he cuts and dries; I can get his number. I don't know know if he would make/sell green beams or not. There is one more individual that has a small timberking bandsaw in the area; I think he strickly custom cuts with it. If you buy some land you may be able to get him or a mutlitude of others to cut them off your property. However if you don't want to go that route and want to buy beams then check with Bibbyman (he's a regular member here) who lives near Fulton; he might be able to hook you up with what you need.

For outside use I wouldn't consider anything but ceader, white oak, osage orange (hedge), or black locust (the kind with thorns); the first two would be the best because you may not be able to find osage orange in long enough sections and both it and locust have a tendency to warp. I would definitely go with white oak if you can get some. White oak has a closed celluar structure (they built ships and barrels from it) and resists rot; red oak has an open celluar structure that sucks water up like a straw and thus rots a whole lot easier.

skylog · December 22, 2004, 07:33:56 PM

Hey Silverback - thanks for all the great info. If it isn't too much trouble (and don't go out of your way to find it) I'd like to have the name of that Amish family and their address if you don't mind. I've got the time to correspond via letter and I suspect the prices and service would be much better. We buy our beef from a Mennonite family over in southern Miami county, and they have a reputation for quality and a fair price.

ARKANSAWYER · December 23, 2004, 07:02:11 AM

SKYLOG,
Pour your slab and make it thick on the edges and put plenty of re-bar in it to handle the weight. Set short pieces of re-bar up so when you set your blocks they will be inside the holes. Mortar the blocks down and fill the holes around the re-bar with concrete. I am doing a frame now that has blocks two high and two wide and is going to be cordwood infilled. We used split faced blocks for a rough face on the outside and will stucco the inside face.
I live in north central Arkansas and saw and build timber frames. I can get you white oak up to 32 ft long and will saw you an order of 10 ft timbers if that is what you need. I cut tennions on my mill for the bottom of the post and cut any size materal you need. Could saw just the sills or the whole thing and oak is far better then white pine and I can cut your timbers from some of the finest yellow pine you have ever seen.
ARKANSAWYER

skylog · December 23, 2004, 03:09:04 PM

Arkansawyer: Thanks for the offer - I am definately interested. Question though - what is a more desirable wood for timberframing, the white oak or the yellow pine? Also, which is the most economical?

I've seen yellow pine in some kit cabins, and it is a pretty wood. I was calling around to some of the lumberyards in the area and asking about lumber/timber pricing, and the lowest prices I found were on the Southern Yellow Pine. None really had any oak to offer in timbers. Would the yellow pine work for timbers and for the infill panels? Would that be the cheapest route? Or should I think about a combination?

Also would like to know what kind of prices I would be looking at?

skylog · December 23, 2004, 03:34:29 PM

Oh yeah, as for the dimensions I will be needing: 6x8 for sills and beams, and 8x8 for the posts. Sills and beams (depending on the final design I settle on) will likely be between 18' and 24'. I don't anticipate needing timbers longer than 24'. Posts will need to be between 9' and 10' to allow for the tenons.

And I will need lots of 6xWhatever for the infill panel logs. I will use anything from 6x6 to 6x12(or larger) for the "panel" logs, depending on whichever is cheapest and most readily available.

ARKANSAWYER · December 24, 2004, 07:44:35 AM

A 6x8x24' white oak sill will run $96.00 and a 18' would be $72.00. Pine is a little cheaper then oak and easier to work and dries out faster as well as shrinks less. White oak is very strong and Southern Yellow pine is up there with the best of them. 8x8x10' in pine is $26.50, in oak is 31.80. 6x8x10' in pine is $20.00, in oak is $24.00. This should give you an ideal of what the cost will be. When you get a full list of timbers send me a IM and I will fill out a quote. This is for "green" bandsawn timber with boxed hearts. Also for a small fee I can square one end and if you do not want to handle a 24 ft timber I can cut the scarf joint on the mill and fit them here.

ARKANSAWYER

skylog · December 24, 2004, 10:05:15 AM

ARKANSAWYER: I have to say that I really appreciate your feedback there. Those prices are good prices and I just want you to know I appreciate you shooting it straight and fair to a new guy.

Question for you - do you know of a way to load those longer timbers (18-24') on an enclosed trailer (24' gooseneck cattle trailer)? Or would I need to rustle up a flatbed trailer?

Also, just thought I'd mention I just talked to my dad and he said he got all his lumber to build our chicken house (large commercial broiler breeder house) down in your area. Said he got quality lumber at a fair price down there.

Second to last question, looks like your yellow pine runs about 17% cheaper than your white oak. Would I be correct in assuming that yellow pine would run $80.00 in 6x8x24' and $60.00 in 6x8x18'?

And last question, is the email listed in your profile the best address to contact you?

ARKANSAWYER · December 24, 2004, 10:34:30 AM

  You be about right on the pricing. I can stick a timber any where you want it ;D or in any trailer you have. No problem.
  The white oak is way more rot proff then the pine but if you block up and seal it off it should work fine.
  You can go up and click on ARKANSAWYER and send a personal message, you can send to the e-mail I have listed or you can go to www.arkansawyer.net and send me a e-mail from there and the phone number is listed on the site. But e-mail is best as I only sit still for short periods of time unless I am deer hunting.
ARKANSAWYER

skylog · December 24, 2004, 11:19:00 AM

Thanks for all your help ARKANSAWYER, I'll be contacting you as soon as I have the plans finalized and a materials list ready. I'll probably be going with the yellow pine, and right now, we're looking to build sometime in late summer/early autumn of '05 if all goes well.

Thanks again - this is a great site - I'm sure we'll cross paths more on here in the coming months.

Silverback · December 27, 2004, 07:07:50 AM

Sweet. Now I don't have to track down that postal address :D I can still get it if you need it but Arky's prices seem real reasonable. That Yellow Pine is also going to be quite a bit lighter if you are attempting to raise it yourself.

I think that he also has a "stamp" if you got those nosey building inspectors. I am so glad that there are still some zone free counties in Missouri.